1. Field of the Invention
This invention relates to an actuator device, and more particularly to an actuator device for actuating an ejector of a scraper.
2. Description of the Prior Art
The ejector of a scraper is used for pushing the earth and sand when discharging them loaded in the bowl thereof on the ground. In general, a large power is required at the start of the operation, whilst a small power can meet the requirement near the end of the operation. Therefore, it is desired that the actuator for operating the ejector can develop a large power at the beginning of its stroke and reduce the power near the end of its stroke, but increase its moving speed.
The prior art actuator device for operating the ejector is disadvantages as disclosed, for example, in U.S. Pat. No. 3,035,361, in that it cannot develop a large power at the start of operation and has a low efficiency because of employing an ordinary actuator.